July 2009doc.: IEEE 802.11-09/0813r2doc.: IEEE 802.11-09/0813r1

IEEE P802.11
Wireless LANs

Update Mesh Peering Protocols
Date: 2009-07-1514
Author(s):
Name / Affiliation / Address / Phone / email
Meiyuan Zhao / Intel Corporation / 2200 Mission College Blvd, Santa Clara, CA95054 / +1 408 653 5517 /

Update clause as indicated in the following:

5.4.3.3 Data Confidentiality

Insert the following paragraph before the paragraph starting at “The default data confidentiality state for all IEEE Std 802.11 STAs is “in the clear”….”

IEEE Std 802.11 provides one security protocol, CCMP, for protection of unicast and group addressed data frames between mesh STAs.

Insert the following paragram at the end of Clause 6.1.2

6.1.2 Security Services

A mesh STA that has associated with dot11MeshSecurityActivated enabled shall not use pairwise cipher suite selectors WEP-40, WEP-104, TKIP.

Insert the following after clause 7.3.1.38:

7.3.1.39 Mesh Peering Protocol Identifier

The Mesh Peering Protocol Identifier field indicates the type of protocol that is currently used to establish peerings. The format of the Mesh Peering Protocol Identifier is shown in Figure s.1.

OUI / Peering protocol identifier value
Octets: 3 / 1
Figure s.1—Mesh Peering Protocol Identifier field

Mesh peering protocol identifier values are defined in Table s.1.

Table s.1—Mesh Peering Protocol Identifier values
OUI / Value / Meaning
00-0F-AC / 0 / Peering Management Protocol
00-0F-AC / 1 / Authenticated Peering Exchange Protocol
00-0F-AC / 2-255 / Reserved
Vendor OUI / 0-255 / Vendor specific

Update Table 7-26 as indicated in the following:

Table 7-26—Element IDs
Information element / Element ID / Total length of element in octets including the Type and Length octets / Extensible
Mesh Configuration Error! Reference source not found. / <ANA 18> / 26
Mesh ID Error! Reference source not found. / <ANA 19> / 2 to 34
Mesh Link Metric Report Error! Reference source not found. / <ANA 20> / 3 to 257
Congestion Notification Error! Reference source not found. / <ANA 21> / 10
Peering Management Error! Reference source not found. / <ANA 22> / 5 to 9
Supported MBSS Regulatory Classes and Channels Error! Reference source not found. / <ANA 23> / 5 to 257
Mesh Channel Switch Announcement Error! Reference source not found. / <ANA 24> / 9
Mesh Awake Window Error! Reference source not found. / <ANA 25> / 4
Beacon Timing Error! Reference source not found. / <ANA 26> / 7 to 257
MCCAOP Setup Request Error! Reference source not found. / <ANA 27> / 7
MCCAOP Setup Reply Error! Reference source not found. / <ANA 28> / 4 or 8
MCCAOP Advertisements Error! Reference source not found. / <ANA 29> / 3 to 257
MCCAOP Reservation Teardown Error! Reference source not found. / <ANA 30> / 3 or 9
Portal Announcement (PANN) Error! Reference source not found. / <ANA 31> / 15
Root Announcement (RANN) Error! Reference source not found. / <ANA 32> / 19
Path Request (PREQ) Error! Reference source not found. / <ANA 33> / 39 to 257
Path Reply (PREP) Error! Reference source not found. / <ANA 34> / 33 or 39
Path Error (PERR) Error! Reference source not found. / <ANA 35> / 14 to 254
Proxy Update (PU) Error! Reference source not found. / <ANA 36> / 11 to 251
Proxy Update Confirmation (PUC) Error! Reference source not found. / <ANA 37> / 10
Authenticated Peering Exchange Error! Reference source not found. / <ANA 38> / 86 to 257
Mesh Peering Protocol Version Error! Reference source not found. / <ANA 39> / 3

Update clause 7.3.2.90 as indicated below:

7.3.2.90 Peering Management element

The Peering Management element is transmitted by a mesh STA to manage a peering with a peer mesh STA. The format of the Peering Management element is shown in Error! Reference source not found..

Element ID / Length / Mesh Peering Protocol Identifier / Subtype / Local Link ID / Peer Link ID / Reason Code
Octets: 1 / 1 / 4 / 1 / 2 / 2 / 2
Figure s25—Peering Management element / Figure s25— / Figure s25—

The Element ID is set to the value given in Element IDs for this information element.

The Mesh Peering Identifier is set to identify the protocol to establish the peering. See 7.3.2.86.8.

The Subtype field specifies the type of the Peering Management element. There are three subtypes: Peering Open (0), Peering Confirm (1), and Peering Close (2). The values 3—255 are reserved.

The Length field is set to a value between 3 and 7 octets and varies depending on the subtype of the Peering Management element. The Length is 3 for Peering Open, and 5 for Peering Confirm. When Peer Link ID is present for Peering Close, the Length is 7. When Peer Link ID is not present for Peering Close, the Length is 5.

The Local Link ID is the integer generated by the local mesh STA to identify the peering instance. This field is present for all three types of Peering Management elements

.

The Peer Link ID is the integer generated by the peer mesh STA to identify the peering instance. This field is not present for the Peering Open subtype, is present for the Peering Confirm subtype, and is optionally present for the Peering Close subtype.

The Reason Code field enumerates reasons for sending a Peering Close. It is present for the Peering Close subtype and is not present for Peering Open or Peering Confirm subtypes. This field enumerates the following reasons:

—PEERING-CANCELLED: SME cancels the peering instance.

—MESH-MAX-PEERS: The limit of maximum of peer mesh STAs is reached.

—MESH-CONFIGURATION-POLICY-VIOLATION: The received request violates the mesh STA’s Mesh Configuration.

—MESH-CLOSE-RCVD: The mesh STA has received a correct Peering Close message (according to criteria defined in Error! Reference source not found.).

—MESH-MAX-RETRIES: The limit of dot11MeshMaxRetries is reached.

—MESH-CONFIRM-TIMEOUT: The confirmTimer times out.The reason code is defined in Error! Reference source not found..

Remove clause 7.3.2.108 (Mesh Peering Protocol Version element)

Update Table s12 as the following:

Table s12—Peering Open frame body
Order / Information / Notes
1 / Category
2 / Action
3 / Mesh Peering Protocol Version
4 / Capability
5 / Supported rates
6 / ERP information / The ERP Information element is present if ERP mesh STA detects NonERP STAs in its vicinity, and is optionally present otherwise.
7 / Extended Supported Rates / The Extended Supported Rates element is present if there are more than eight supported rates, and is optionally present otherwise.
8 / Power Capability / The Power Capability element is present if dot11SpectrumManagementRequired is true.
9 / Supported Channels / The Supported Channels element is present if dot11SpectrumManagementRequired is true and dot11ExtendedChannelSwitchEnabled is false.
10 / RSN / The RSN information element is present only if dot11RSNAEnabled is set to TRUE.
11 / Mesh ID
12 / Mesh Configuration
13 / Peering Management / The subtype of the Peering Management element is set to 0.
14 / Authenticated Peering Exchange / The Authenticated Peering Exchange element is present when dot11MeshSecurityActivated is true.
15 / MIC / This field is present when dot11MeshSecurityActivated is true.
16 / HT Capabilities / The HT Capabilities element is present when dot11HighThroughputOptionImplemented is true.
17 / HT Information / The HT Information element is included when dot11HighThroughputOptionImplemented is true.
18 / Extended Capabilities element / The Extended Capabilities element is present if the dot112040BSSCoexistenceManagementSupport is true and is optionally present otherwise.
19 / 20/40 BSS Coexistence element / The 20/40 BSS Coexistence element is present when the dot112040BSSCoexistenceManagementSupport is true.
20 / Supported MBSS Regulatory Classes and Channels / The Supported MBSS Regulatory Classes and Channels element is present if dot11ExtendedChannelSwitchEnabled is true.
Last / Vendor Specific / Optionally present: one or more vendor-specific information elements. This information element follows all other information elements.

Update Table s13 as the following:

Table s13—Peering Confirm frame body
Order / Information / Notes
1 / Category
2 / Action
3 / Mesh Peering Protocol Version
4 / Capability
5 / AID
6 / Supported rates
7 / Extended Supported Rates / The Extended Supported Rates element is present if there are more than eight supported rates, and is optionally present otherwise.
8 / RSN / The RSN information element is present only when dot11RSNAEnabled is set to TRUE.
9 / Mesh Configuration
10 / Peering Management / The subtype of the Peering Management element is set to 1.
11 / Authenticated Peering Exchange / The Authenticated Peering Exchange element is present when dot11MeshSecurityActivated is true.
12 / MIC / This field is present when dot11MeshSecurityActivated is true.
13 / HT Capabilities / The HT Capabilities element is present when dot11HighThroughputOptionImplemented is true.
14 / HT Information / The HT Information element is included when dot11HighThroughputOptionImplemented is true.
15 / Extended Capabilities element / The Extended Capabilities element is present if the dot112040BSSCoexistenceManagementSupport is true, and is optionally present otherwise.
16 / 20/40 BSS Coexistence element / The 20/40 BSS Coexistence element is present when the dot112040BSSCoexistenceManagementSupport is true.
Last / Vendor Specific / Optionally present: one or more vendor-specific information elements. This information element follows all other information elements.

Update Table s14 as the following:

Table s14—Peering Close frame body
Order / Information / Notes
1 / Category
2 / Action
3 / Mesh Peering Protocol Version
4 / Mesh ID
5 / Reason code
6 / Peering Management / The subtype of the Peering Management Element is set to 2.
7 / Authenticated Peering Exchange / The Authenticated Peering Exchange element is present when dot11MeshSecurityActivated is true.
8 / MIC / This field is present when dot11MeshSecurityActivated is true.
Last / Vendor Specific / Optionally present: one or more vendor-specific information elements. This information element follows all other information elements.

Update clause 8.4.1.1.2a as indicated in the following:

8.4.1.1.2a Mesh TKSA

The Mesh TKSA is a result of the Authenticated Peering Exchange. This security association is also bidirectional. The Mesh TKSA shall be deleted when the lifetime expires. The Mesh TKSA contains the following elements., and is identified by MTKName.

—MTK, as defined in Keys and Key Derivation Algorithm

—MTKName

—PMKName

—local mesh STA MAC address

—peer mesh STA MAC address

—local Link ID

—peer Link ID

—local nonce

—peer nonce

—Lifetime

—Pairwise cipher suite selector

Update clause 8.9.1 as indicated in the following:

8.9.1 Keys and Key Derivation Algorithm

To execute the Authenticated Peering Exchange, the mesh STA shall derive the keys, including a key encryption key (AKEK), a key confirmation key (AKCK), and a mesh temporal key (MTK) using the chosen PMK.

The AKEK and AKCK are derived statically from the chosen PMK. The MTK is derived based on dynamic information provided by localNonce and peerNonce.

AKCK and AKEK are mutually derived by the local mesh STA and the peer mesh STA once a new PMK has been selected. The AKCK is used to provide data origin authenticity in the Authenticated Peering Exchange and the Group Key Handshake messages. The AKEK is used to provide data confidentiality in the Authenticated Peering Exchange and the Group Key Handshake messages.

The AKEK and AKCK shall be derived from the PMK by

AKCK || AKEK  KDF-384(PMK, “AKCK AKEK Derivation”, Selected AKM Suite || min(localMAC, peerMAC) || max(localMAC, peerMAC))

The min and max operations for IEEE 802 addresses are with the address converted to a positive integer, treating the first transmitted octet as the most significant octet of the integer as specified in 8.5.1.2.

The AKCK shall be computed as the first 128 bits (bits 0—127) of the resulting string:

AKCK  L(AKCK||AKEK, 0, 128)

The AKEK shall be computed as the next 256 bits (bits 128-383) of the resulting string:

AKEK  L(AKCK||AKEK, 128, 256)

The temporal key (MTK) shall be derived from the PMK by

MTK  KDF-X(PMK, “Temporal Key Derivation”, min(localNonce, peerNonce) || max(localNonce, peerNonce) || min(localLinkID, peerLinkID) || max(localLinkID, peerLinkID) || Selected AKM Suite || min(localMAC, peerMAC) || max(localMAC, peerMAC))

CCMP uses X = 128. The Min and Max operations for IEEE 802 addresses are with the address converted to a positive integer treating the first transmitted octet as the most significant octet of the integer as specified in 8.5.1.2. The Min and Max operations for nonces are with the nonces treated as positive integers converted as specified in 7.1.1.

The MTK is used to protect communications between two peer mesh STAs. The local mesh STA and peer mesh STA normally derive a MTK only once per peering instance. The local mesh STA or peer mesh STA may use the Authenticated Peering Exchange to derive a new MTK.

The MTK is referenced and named as follows:

MTKName = NDF(PMKName || “TK Name” || min(localNonce, peerNonce) || max(localNonce, peerNonce) || min(localLinkID, peerLinkID) || max(localLinkID, peerLinkID) || Selected AKM Suite || min(localMAC, peerMAC) || max(localMAC, peerMAC)

PMKName is the identifier of the chosen PMK.

Update the first bullet in clause 11C.3.2.4.2 as indicated in the following:

11C.3.2.4.2 Peering Open frame contents for Authenticated Peering Exchange

A mesh STA initiates the establishment of a peering and Mesh TKSA with a candidate peer mesh STA by sending a Peering Open frame to the candidate peer mesh STA. In addition to contents for establishing a peering as specified in Peering Open frame contents, the Peering Open frame shall contain the following:

—Mesh Peering Protocol Version, which In the Peering Management information element, the Mesh Peering Protocol Identifier shall be set to 00-0F-AC:Error! Reference source not found. “Authenticated Peering Exchange Protocol”.

Update the first bullet in clause 11C.3.2.4.5 as indicatd in the following:

11C.3.2.4.4 Peering Confirm frame content for Authenticated Peering Exchange

When sending a Peering Confirm frame in response to a Peering Open frame, the constructed Peering Confirm frame shall contain the following in addition to contents for establishing a peering as specified in Peering Confirm frame contents.

—Mesh Peering Protocol Version, which In the Peering Management information element, the Mesh Peering Protocol Identifier shall be set to 00-0F-AC:Error! Reference source not found. “Authenticated Peering Exchange Protocol”.

Update the first bullet in clause 11C.3.2.4.6 as indicatd in the following:

11C.3.2.4.6 Peering Close frame content for Authenticated Peering Exchange

When sending a Peering Close frame, the mesh STA shall generate additional information for Authenticated Peering Exchange, specified as following:

—Mesh Peering Protocol Version In the Peering Management information element, the Mesh Peering Protocol Identifier shall be set to 00-0F-AC:Error! Reference source not found. “Authenticated Peering Exchange Protocol”.

Insert the following at the end of clause 11C.3.1 as indicated in the following

11C.3 Mesh link security[m1]

11C.3.1 Overview

Security protocol, CCMP, shall be used for protection of unicast and group addressed data frames between mesh STAs.

Insert the following before the first paragraph in clause 11C.3.2.2.1 as indicated below

11C.3.2.2.1 Instance Pairwise Cipher Suite Selection

Pairwise cipher suite selectors WEP-40, WEP-104, and TKIP shall not be used as the pairwise cipher suite when dot11MeshSecurityActivated is enabled.

If the pairwise cipher suite has not been selected, mesh STAs shall attempt to reach the agreement on the pairwise cipher suite using the following procedure in four phases:

Insert the following paragraph at the beginning of clause 11C.3.2.2.2 as indicated below

11C.3.2.2.2 Group Cipher Suite Selection

Group cipher suite selectors WEP-40, WEP-104, and TKIP shall not be used as the group cipher suite when dot11MeshSecurityActivated is enebled.

Update clause as indicated in the following:

11C.4.4 Pre-processing Peering Management Frames

Each peering instance shall be identified by the peering instance identifier. The MPM FSMs are identified by a set of data including localLinkID, peerLinkID, localMAC, and peerMAC. The Authenticated Peering Exchange FSMs are identified by localNonce, peerNonce, and PMKName, in addition to the data set for peering instance identifier.

The mesh STA shall pre-process the incoming peering management frame. As the result, the mesh peering instance controller shall either discard the frame or pass it to the corresponding active peering instance finite state machine for further processing.

If the Mesh Peering Protocol Identifier is set to “Peering Management Protocol”, Peering Management information element shall be pre-processed to identify the peering instance. In addition, the Authenticatd Peering information element and MIC, if present, shall be ignored.

If the Mesh Peering Protocol Identifier is set to “Authenticated Peering Exchange”, the Peering Management information element, RSN information element, and Authenticated Peering Exchange information element shall be pre-processed to identify the peering instance. The frame shall be silently discarded if the Authenticated Peering Exchange or MIC information element doesn’t exist in the frame.

If the frame contains a group address in TA or RA, it shall be silently discarded.

The instance identifier in the frame shall be processed next. The incoming peering management frame belongs to an active peering instance, if the peering identifier in the incoming frame matches an existing active peering instance. To match a peering instance,

—If a peering instance is identified by MAC addresses and Link IDs by both mesh STAs

—The sender’s MAC address shall be the same as the peerMAC of the peering instance

—The receiver’s MAC address shall be the same as the localMAC of the peering instance

—The value of Local Link ID field shall be the same as the peerLinkID of the peering instance

—The value of Peer Link ID field (if exists) shall be the same as the localLinkID of the peering instance

—If the matching fails, and there exists a peering instance that is identified by only the localMAC and localLinkID, the incoming Peering Open frame or Peering Close frame with no value set to Peer Link ID field shall match this peering instance and the peerMAC and peerLinkID of the peering instance are set accordingly.

If the incoming peering management frame is for Authenticated Peering Exchange (as specified in Peering Protocol Version Mesh Peering Protocol Identifier field in the Peering Management information element), the identifier shall further match the identifier for Authenticated Peering Exchange. If the chosen PMK from the frame is different than the PMKName that identifies the mesh PMKSA that the mesh STA establishes with the candidate peer mesh STA, the incoming frame is a mismatch.

If the received chosen PMK is a match, the mesh peering instance controller shall further examine the nonces in the frame.

—If the matched peering instance by MAC addresses and Link IDs has also peerNonce, the incoming frame is a match if

—The value of Local Nonce field shall be the same as the peerNonce of the peering instance, and

—The value of Peer Nonce field (if exists) shall be the same as the localNonce of the peering instance

—If the matched peering instance by MAC addresses and Link IDs does not have peerNonce, the incoming Peering Open frame or the Peering Close frame with no value set to Peer Nonce field shall match this peering instance. The peerNonce of the peering instance is set accordingly.